I bought this separator to use with a siphon-fed spray gun I purchased. As with any air connection I make I used gas sealant tape (similar to Teflon tape) when i connected this to my sprayer. I do not have any other filter on my compressor line as I do not do much painting with it. This oil and water separator worked flawlessly to trap the moisture coming through the hose which meant I ended up with a flawless paint job. I was also painting on a some what humid day which would leave even more moisture in my compressor tank. This product is inexpensive enough that you could purchase several to install on other tools instead of swapping it out, or you could just install it on the end of your hose. I would not hesitate to purchase again.